Earthing and the Autonomic Nervous System
Research has shown migraine to be caused by dysfunction in the sympathetic nervous system. The autonomic nervous system, the connection between the brain and the gut is now also thought to play a major role. One of the effects of earthing is to calm and rebalance these systems.
The 2011 study Emotional Stress, Heart Rate Variability, Grounding, and Improved Autonomic Tone: Clinical Applications (Chevalier, G. Sinatra, S.) looked at the effects of earthing on heart rate variability, a measure of autonomic nervous function.
It took 28 relatively healthy subjects who were seated in a comfortable recliner and grounded to earth via conductive patches on their hands and feet. They remained ungrounded for the first 40 minutes, followed by 40 minutes grounded and then a further 40 minutes ungrounded. During this time they had their heart rate variability measured by ECG.
The study found that heart rate variability improved significantly during the grounded period, suggestive of improvement in the autonomic nervous system.
This 2010 study was of a similar design but measured pulse rate, respiratory rate, blood oxygenation, perfusion index and skin conductance. It found differences in all of these factors following earthing, but perhaps the most significant was the decrease in skin conductance which happened almost immediately as earthing was commenced.
Raised skin conductance is a measure of overstimulation of the sympathetic branch of the autonomic nervous system. Therefore, this dramatic reduction confirms the regulatory effects of earthing on this.